Rock Wren

The rock wren (Salpinctes obsoletus) is the  only species in the genus Salpinctes.
A small songbird of the wren family, the adult rock wren is almost five inches long, with grey-brown upperparts and white and black dotted  pale grey underparts, merging into a light brown or cinnamon rump. There are buffy tips on their outer feathers, and they sport a broad dark tail band. These birds have a light grey line over each eye on a head that is dull grey-brown on crown and nape.  The face of a rock wren is greyish and finely spotted with white and dark. The chin and throat are whitish. They have a long slightly decurved thin bill, a long barred tail and dark legs.
They range from southwestern Canada south to Costa Rica, though on occasion some will vagrant for a season in the Eastern United States.  The northern populations from the central Unitied States and Canada migrate to warmer areas in the south in the late fall and winter. But some are permanent residents in warmer habitats, including those in San Bernardino County.
They are fond of arid or semiarid areas with exposed rock; desert to alpine habitats.
They actively forage on the ground, around and under objects, probing with their bill as their extraction too, gleaning its prey from rocks and sometimes poaching insects from spider’s webs. It’s primary diet is insects, but will dine upon spiders if they can be found.  They often bounce up and down among rocks while feeding. The rock wren will also capture flying insects by hopping vertically from the ground. On the ground, it will probe with its bill for food, mainly insects and earthworms. The Rock Wren does not drink water, but instead hydrates from its food.When five rock wrens were pent up in a cage together, the supply of water provided to them did not diminish at all, as they did not sip from it.
They seek out dry rocky locations, including canyons, for breeding grounds, building a cup nest in a crevice or cavity, usually among rocks. A pavement or walkway of small, flat stones or pebbles is usually constructed by the rock wren to lead to the nest cavity. Though the nest is normally contained in a crevice that is out of sight, this walkway betrays the nest’s location.Ornithologists have yet to ascertain what the function of this pavement is.
During breeding season, a male establishes its territory and sings from rock promontories to attract females. Each pair is monogamous and solitary nester, and lasts through one season.
Rock wrens have a remarkably varied trill, which becomes ever more so during the nesting season. The male rock wren boasts an impressive repertoire of 100 or more song types, including buzzes, trills, chatters and whistles, many of which seem to be imitations of other birds or sounds in nature or man-made ones, such as cell phone rings.
The female lays five to six glossy white eggs, finely spotted of reddish-brown. Incubation lasts about 14 to 16 days, by female alone, occasionally fed by the male. Altricial chicks are fed by both parents during about two weeks. The young fledge at about 14 to 16 days of age, and parents feed them for about a week.
At this time, young become independent for food, but they remain for about one month in the parents’ territory.
This species may produce two to three broods per year.
A rock wren bobs its body upon being alarmed.  Like a woodpecker, the rock wren roosts in vertical posture.
As a species, the rock wren appears to be declining throughout some parts of its range. Birds are preyed upon by snakes and mammals. However, the rock wren remains currently widespread and common, even with increased incidence of nest parasitism by the brown-headed cowbird.
A group of wrens is referred to by many collective names, such as a “chime,” “flight,” “flock,” and “herd” of wrens.

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